298 DETECTION OF ADULTERANTS AND PRESERVATIVES 



L, = Quevenne lactometer reading at 60 degrees F. ; f = per 

 cent fat ; t = total solids ; s = specific gravity of milk. 



Example of milk that is normal Quevenne lactometer reading 

 at 60 degrees F. 32, fat 4 per cent. 



Answer : 



Specific gravity of the milk = 1.032 



Total solids -^--+ 1.2 X 4= 12.8 per cent. 



32 

 Solids not fat 1- .2 X 4 = 8.8 per cent. 



Specific gravity of milk solids 

 12.8 



12.8 100 X 1.032100= 1.32 



1.032 



Example of milk to which water has been added. Quevenne 

 lactometer reading at 60 degrees F. 26, fat 3.8 per cent. 



Answer : 



Specific gravity of milk = 1.026 



Total solids^-- + 1.2 X 3.8 = 11.06 per cent. 



26 

 Solids not fat + .2 X 3.8 7.26 per cent. 



Specific gravity of milk solids 

 11.06 



11.06 100 X 1.026100= 1.295 



1.026 



Example of milk from which cream was removed or to which 

 skimmed milk was added. Quevenne lactometer reading at 60 de- 

 grees F. 35, fat 2 per cent. 



